Multi body design limitations (?)

In the past, I made use of the split part command to split parts into linked sub parts. For example, I make installation templates that are used to make drilling holes to anchor our machines to concrete floors. The templates are usually several feet long so I split them up to make the easier to handle. With multi-body, replacing split part, a different approach is required. This is my first venture into multi-body and it seems to be more difficult to work with than split part. For example, I put some oval cutouts in the template halves for handles. In the past, I would create one cutout and then mirror it over to the other side, update the linked parts and move on. Now, I'm finding that multi-body won't let me do that. Am I missing something? Here is an image of the template and you can see the obround cutout I want to mirror. It's a simple part and this was a 5-10 minute job with previous split part tool.

Re: Multi body design limitations (?)

Has anyone else noticed the odd limitation of the split part command? - it doesn't let you split a single body with two solids into two bodies i.e. if you were to extrude two circles to make two separate cylinders (but just one body as far as SE is concerned), you can't split them into two bodies.

Does anyone know a way around this? Obviously my example is trivial - in this case you'd just extrude one, then add body and extrude the other.